Two teenagers have been arrested in Pakistan over the death of a four-year-old girl last month which triggered protests across the country.

The suspects confessed to trying to sexually assault the girl in a sugarcane field and then strangling her when she cried out, according to Silahuddin Mehsud, police chief in the Khyber Pakhtunkhwa province.

He added that one of the suspects was a relative of the victim.

Pakistan has seen a wave of protests in recent weeks over alleged police negligence.

The demonstrations were initially ignited by the rape and murder of a seven-year-old girl in the city of Kasur, whose body was found on a rubbish heap. Police have arrested an alleged serial killer believed to have murdered her and seven other children.